Can Human Urine Replace Chemical Fertilizers?

urine harvesting field

Human urine as a replacement for chemical fertilizers. Urine contains nitrogen, phosphorus and potassium — essential plant nutrients that are usually mined from the earth or the air for agricultural use. In collecting human urine, Rich Earth is diverting the same chemicals from waterways to farms, making a potentially harmful substance a boon to crop production.

As urine collection schemes are difficult and challanging to manager due to lack of volunteer, Nuleaf projects offers the technology to collect undulated urine , which hosts the so-called “urine depot.” There is a buzz of conversation as waterless urinal users when people realize that they produce

something every day that can be helpful to the environment and the earth, it’s a very wonderful feeling.

Across the World, studies have long established urine as a powerful fertilizer. A study conducted by the Stockholm Water Company in the late 1990s diverted urine from four housing projects to a grain farmer outside the city. The scientists concluded not only that urine could replace quick-acting mineral fertilizers, but also calculated that one Northern European adult pees enough plant nutrients to grow 50 to 100 percent of the food requirement for another person. Other successful trials have taken place in China and Mexico, though none as detailed as the Swedish one

Health Aspects/Acceptance

Urine poses a minimal risk of infection, especially when faecel cross contamination during source separation is avoided and it has been stored for an extended period of time. Yet, urine should be carefully handled and should not be applied to crops less than one month before they are harvested. This waiting period is especially important for crops that are consumed raw.

Social acceptance may be difficult. Stored urine has a strong smell and some may find it offensive to work with it or to have it nearby. If urine is diluted and/or immediately tilled into the earth, however, its smell can be reduced. The use of urine may be less accepted in urban or peri-urban areas when household gardens are close to peoples’ homes than in rural areas where houses and crop land are kept separate.

Operation & Maintenance

Over time, some minerals in urine will precipitate (especially, calcium and magnesium phosphates). Equipment that is used to collect, transport or apply urine (i.e., watering cans with small holes) may become clogged over time. Most deposits can easily be removed with hot water and a bit of acid (vinegar), or in more extreme cases, manually chipped off.

Applicability

Urine is especially beneficial for crops lacking in nitrogen or requiring a lot of nitrogen to grow. Examples of some crops that grow well with urine include: maize, rice, millet, sorghum, wheat, chard, turnip, carrots, kale, cabbage, lettuce, bananas, paw-paw, and oranges. Urine application is ideal for rural and peri-urban areas where agricultural lands are close to the point of urine collection. Households can use their own urine on their own plot of land. Alternatively, if facilities and infrastructure exist, urine can be collected at a semi-centralized location for distribution and transport to agricultural land. Regardless, the most important aspect is that there is a need for nutrients from fertilizer for agriculture which can be supplied by the stored urine. When there is no such need, the urine can become a source of pollution and a nuisance.

Advantages

May encourage income generation (improved yield and productivity of plants)